A case of acute aniline poisoning treated with commercially available intravenous methylene blue

Abstract

Acute aniline poisoning can cause methemoglobinemia. We report a case of acute aniline poisoning showing rapid improvement following treatment with commercial intravenous methylene blue solution. A 59-year-old male complaining of headache and nausea was rushed to the emergency room. He was working as a cleaner without using proper personal protective equipment in a chemical plant where aniline was used. His breathing and circulation were normal, but his whole body was discolored blue, and his SpO₂ was as low as 87％. The arterial blood gas analysis revealed a PaO₂ of 153 mmHg and SaO₂ of 97％, indicating that his oxygenation was fine, but the color was extremely dark, like chocolate. The methemoglobin level was found to be elevated to 44.5％. He showed improvement in his cyanosis, saturations, and clinical symptoms following intravenous administration of commercially available methylene blue.